I think this is worth adding as well:
Ensure RTL to takeoff, not startup location. Prior to this it would record startup location as HOME, now it will record arming location
Allow use of full ESC output - This is great if it was fully tested, prior to this PWM range was limited more due to ESC design issue, now it is limited less, if not full
Arming fixes - magnetic anomaly will not fail GPS checks, lessens surface with large magnetic anomaly fails.
Arming fixes - will not perform IMU calibration when arming
Movement of the copter on loose surfaces can cause the calibration to fail and prevent takeoff/.
The calibration is not required because the EKF learns gyro biases after power up.
The calibration is blocking and will cause errors in the inertial nav solution if the vehicle changes orientation during arming.
Making the arming non-blocking whilst retaining the 2 sec delay from passing arming checks to starting motors required
Various fixes to GPS glitch and failsafe